As is well known, a ship or other object which floats in a body of water changes its position with respect to a stationary object, such as a dock or pier, as the level of the body of water changes. The change in water level is generally associated with tides, but other causes can also influence the water level.
Movement of personnel and/or cargo between an object floating on the surface of a body of water and shore generally occurs via a stairway or a gangway. The stairway generally has one end thereof associated with the floating object and another end thereof associated with a stationary or fixed object on the shore. As the floating object moves under the influence of the changing water level, the angular orientation of the stairway with respect to both the floating object and the fixed object will change.
Accordingly, the art contains several examples of gangways or stairways that change their angles of orientation as a floating object moves under the influence of a changing water level. While somewhat successful, these known devices have several drawbacks. Specifically, the gangways known to the inventor do not maintain the walking surface thereof level as the gangway changes its angular orientation in an adequate and efficient manner. Therefore, someone using these known gangways must remain alert to a walking surface that may not be as level as necessary or may not be in the expected position.
Still further, the known stairways do not provide adequate handgrip means for a user. Ideally, the handgrip means should remain parallel to the walking surface as the stairway moves whereby a user can hold onto a handrail that is parallel to the walking surface.
Therefore, there is a need for a stairway for connecting a floating member to a stationary member and which maintains its walking surface or surfaces horizontal as the stairway changes its angular orientation. There is a further need for such a stairway which also includes handrails that remain parallel to the walking surface as the stairway changes its angular orientation.